1. Field of the Invention
The present invention relates generally to the modulation of hyaluronan (HA) synthesis and degradation. More particularly, the present invention provides compositions and methods for modulating the expression of genetic material encoding HA synthase (HAS) and other enzymes or receptors primarily involved in hyaluronan metabolism; or modulating the proteins that synthesise or degrade hyaluronan including HAS function or activity. The compositions include or comprise nucleic acid molecules and interactive molecules such as antibodies and small molecule inhibitors and HAS substrate analogs. The present invention further contemplates modulation of cellular proliferation, useful in the prophylaxis and/or treatment of inflammatory disorders including hyperproliferative conditions, such as but not limited to, cancer and psoriasis
2. Description of the Prior Art
Bibliographic details of the publications referred to in this specification are also collected at the end of the description.
Reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the general knowledge in any country.
Inflammatory conditions represent a major causative factor in numerous medically significant disorders. Inflammation can result from a range of stimuli from outside or within the body. However, these stimuli trigger cells and physiological processes within a host environment. Whilst a substantial amount of research has been undertaken to investigate the cellular and cytokine nature of inflammatory processes, less is known about other possible participants in inflammation.
One such class of participants is transmembrane proteins. Transmembrane proteins are involved in a range of signalling activities and many have anzymic activity.
Hyaluronan (HA) metabolism is an intricate balance between the rate of HA synthesis and degradation where depending upon the physiological role being played by the HA, the simulateneous synthesis and degradtion is carefully controlled. Hyaluronan is synthesised by a family of distinct yet related transmembrane proteins termed hyaluronan synthase (HAS) isoforms HAS1, 2 and 3, which can be distinguished from one another with respect to temporal and differential expression during mouse embryogenesis and in mature tissues, respectively and also in the molecular weight of the HA produced. The extracellular matrix polysaccharide HA or its acidic form, hyaluronic acid, is a linear, high molecular weight polymer comprised of repeating disaccharide units of (β1-3) D-glucuronate-β1-4)N-acetyl-D-glucosamine (Weissman & Meyer, J. Am. Chem. Soc.76: 1753, 1954). Hyaluronan is degraded by a family of enzymes known as hyaluronidases which are currently termed HYAL1, HYAL2, HYAL3 and PH-20, where like the enzymes which produce HA are also distinguished from one another with respect to temporal and differential expression during different physiological processes and disease states.
In work leading up to the present invention, it was observed that HAS and HYAL are differentially expressed under various physiological conditions. In particular, they were up-regulated during disease conditions such as an inflammatory condition or cancer. HAS, and in particular, HAS1, 2 and/or 3 and HYAL1, 2 and/or 3 represent useful drug targets.